If the 3rd and 4th cans are removed, and the drip pan and grate are mounted directly on the Weber can, as in this photo, the water simmers, but will not maintain a boil. The heat from a candle is greatest just above the flame tip. The same seems to be true here as well.
The time from ignition to dumping the biochar into the quench can was 81 minutes. Right in the expected range.
Tomorrow I will show you how elegant this looks from a standing position. If a cabinet were built around this such that only the gas drip pan and grate showed on top, it would look very 'sexy' and modern. Of course, it would be required that you could easily remove all of the parts below the drip pan for easy refueling, biochar capture, and maintenance. This should be fairly straight forward as the C4 design is very well behaved and the flame and heat are well managed. There is almost no heat expressed laterally and the flame stays with in the system until it exits the hole in the drip pan. It is quite beautiful, even if I do say so myself.